Permanent magnet synchronous motor (PMSM) and the inverters and controllers are important parts of the platform’s power system, and the vibration and noise indicators have a great impact on the realization of the platform’s quality goals. Due to factors such as the non-ideal pole-slot combination and the poor sinusoidal degree of the air gap flux density, the winding current will contain the 5th and 7th harmonics, which will cause the motor to produce harmonic torque pulsation as well as vibration and noise. In order to reduce the vibration and noise of PMSM during the operation, a novel harmonic suppression strategy is discussed, in which the harmonic current is injected into the phase current of the PMSM system to generate harmonic torque, thereby canceling the existing low-order harmonic torque ripple. The effectiveness of this strategy is verified by simulation and experiment.